Recent Developments in Isolation Hardware

Abstract: Most isolation systems have at least two physical components: one specifically intended to add flexibility and the other to control the resulting deflections. However, other elements may also be necessary such as a wind restraint, a back-up safety device and an element to restrain uplift and/or excessive horizontal displacements. For building structures, flexible couplings for utility lines are required as well as special details for elevators tracks, window mullions and access ramps or steps. This paper summarizes recent developments in this field, especially work in progress in the United States, Japan and New Zealand. A brief review of the following hardware is therefore made: elastomeric bearings, rollers and sliding plates, metals in plastic deformation, fillers in rubber compounds, viscous flow in fluids, and friction between sliding surfaces.